Therapeutic bed

ABSTRACT

A therapeutic bed ( 1 ) comprises a patient support platform ( 7 ) rotatably mounted on a base frame ( 4 ) for rotation about a longitudinal pivot axis between a supine support position and a prone support position. The base frame ( 4 ) is in turn mounted on a wheeled chassis ( 2 ) by pivot linkages ( 5 ) which allow tilting and raising and lowering of the base frame ( 4 ) on the chassis ( 2 ). Drive interlocks prevent rotation of the patient support platform ( 7 ) unless side rails ( 25 ) are locked on the patient support platform ( 7 ) and patient support flaps ( 40, 41 ) extending between the side rails ( 25 ) are locked together to secure a patient on the patient support platform ( 7 ). Guides ( 51 ) are provided at each end of the patient support platform ( 7 ) at the longitudinal rotational axis to guide patient care lines between a patient on the patient support platform ( 7 ) and associated devices externally of the patient support platform ( 7 ). This prevents entanglement of patient care lines as the patient support platform ( 7 ) rotates.

BACKGROUND OF THE INVENTION

This application claims priority to PCT/IE99/00049 filed Jun. 3, 1999,which entered the United States national stage on Jun. 28, 2001. Thisapplication also claims priority to PCT/IE96/00087 filed Dec. 17, 1996,which entered the United States national stage on Jun. 18, 1998, and acontinuation of U.S. patent application Ser. No. 09/099,397 filed Jun.18, 1998, which issued as U.S. Pat. No. 6,112,349 on Sep. 5, 2000. Thisapplication also claims priority to Ireland application 950950 filed onDec. 18, 1995, on which PCT/IE96/00087 is based, and also claimspriority to Ireland application S980415 filed on Jun. 3, 1998.

BACKGROUND OF THE INVENTION

This invention relates to a therapeutic bed, and in particular to pronepositioning beds.

Patient positioning has been used for some time as a treatment forpatient comfort, to prevent skin breakdown, improve drainage and tofacilitate breathing. One of the goals of patient positioning has beenmaximisation of ventilation to improve systematic oxygenation. Variousstudies have demonstrated the beneficial effects of body positioning andmobilisation on impaired oxygen transport. The support of patients in aprone position can be advantageous in enhancing extension andventilation of the dorsal aspect of the lungs.

The present invention particularly relates to therapeutic beds of thetype comprising a base frame, a patient support platform rotatablymounted on the base frame for rotational movement about a longitudinalrotational axis of the patient support platform, and drive means forrotation of the patient support platform on the base frame.

In our previously filed patent application, publication no. WO 97\2323,we described a therapeutic bed of this type for supporting a patient ineither a supine position or a prone position and for using kinetictherapy.

This type of bed is particularly suited for the treatment of patientswith respiratory problems. The beds advantageously allow rotation of thepatient on the patient support platform and, where required, rotation ofthe patient support platform into a prone support position which isparticularly desirable in the treatment of patients with severerespiratory problems.

In such therapy, a patient may be heavily intubated with a number oftubes extending over a side of the bed between the patient on the bedand associated apparatus mounted on stands or the like alongside the bedfor either delivering liquids to the patient or draining liquids fromthe patient. Also, there may be a number of wires extending from sensorson the patient to various monitors adjacent the bed. These ventilationand drainage tubes, medication supply tubes, monitoring cables and thelike are collectively called patient care lines throughout this patentspecification. The term “patient care lines” as used in this patentspecification is taken to mean any tubes, pipes, conduits, cables andthe like lines for delivery or drainage of fluids to or from a patient,for monitoring a patient's condition and generally speaking for treatinga patient on the patient support platform of the bed. These patient carelines present a problem, particularly when rotating the patient supportplatform between a supine support position and a prone support position,in that they can easily become entangled and may be inadvertently pulledaway from the patient. To avoid this a nurse or other attendant has tocarefully handle and adjust the patient care lines as necessary whilstthe bed is rotating. This can be extremely awkward. Access to thepatient and the patient care lines is difficult when the patient supportplatform is at or approaching the prone support position.

Another problem that arises is in ensuring that the patient is correctlysecured to the patient support platform before rotating the patientsupport platform away from a horizontal supine support position. Again,a nurse has to check all the patient retaining strapping, rails andsupports are secure prior to rotation of the patient support platforminto the prone support position. This tends to be very time consuming.Also, it is not always easy to check the strapping or other restraintsare correctly and securely engaged.

To rotate the patient support platform between the supine supportposition and the prone support position, typically a number of nursingstaff are required to rotate the patient support platform and at thesame time, handle the tubing and wiring to prevent entanglement ordislodgement. Thus, a number of nursing staff may be diverted from otherduties for a considerable time. Consequently, the operational efficiencyis adversely effected and costs increased for the hospital.

The present invention is directed towards overcoming these problems.

SUMMARY OF THE INVENTION

Accordingly, a therapeutic bed operable to provide lateral rotationaltherapy in both the prone and supine positions is provided having aframe, a patient support platform mounted on the frame and rotatableabout a longitudinal axis of rotation through substantially 180° from apatient face-up or supine position to a patient face-down or proneposition, and a motor operationally engaged with the patient supportplatform to provide controlled rotational movement to the patientsupport platform. In one embodiment, the patient support platformcomprises a hinged section that provides access to the back of a patientwhen the patient support platform is in the patient face-down or proneposition. In another embodiment, the patient support platform comprisesside rails that can be locked into place or that can be removed tofacilitate mounting of patients on the patient support platform. Thetherapeutic bed also comprises a plurality of prone patient supports,including a head support, an abdomen support comprised of flexiblematerial and which is adjustable to accommodate abdomens of varyingsizes, and support pad sections that are split longitudinally to defineadjustable support parts that are hingedly mounted to the correspondingopposite side rails. At least some of the prone patient supports areoperable to be locked to each other with straps and fasteners. The headsupport includes a strap to support the patient's head. Many of theprone patient supports are separately adjustable.

In another embodiment, a therapeutic bed operable to provide lateralrotational therapy to a patient in both the supine and prone positionsis provided comprising a frame; a patient support assembly mounted onthe frame; wherein the patient support assembly comprises a patientsupport platform mounted on a circular structure having a center and aperimeter; and a motor operationally engaged with the patient supportassembly to provide controlled rotational movement to the patientsupport assembly. The patient support assembly is rotatable about alongitudinal axis of rotation through substantially 180° from a patientface-up or supine position to a patient face-down or prone position;wherein the longitudinal axis of rotation of the patient supportassembly is coaxial with the circular structure. The load from thepatient support assembly is transferred to the frame through theperimeter of the circular structure. The circular support may compriseone or more ring-shaped rails mounted on guide rollers on the frame.Alternatively, the perimeter of the circular support may becylindrically shaped or barrel-shaped.

Accordingly, an apparatus and method for treating a patient withrespiratory problems, and in particular, adult respiratory distresssyndrome, is provided in which a patient may be secured to amechanically powered patient support platform; the patient rotated froma substantially supine position to a substantially prone position; andthe patient alternately laterally rotated about a longitudinal axis ofthe bed across an arc spanning from between positive 15 to 62 degreesfrom the prone position to a negative 15 to 62 degrees from the proneposition.

The invention is characterised in that there is provided guide means forpatient care lines at one or both ends of the patient support platformfor guiding the patient care lines between a patient on the patientsupport platform and associated apparatus externally of the patientsupport platform, said guide means being mounted at or adjacent thelongitudinal rotational axis of the patient support platform.

Advantageously, the invention provides a bed incorporating a patientcare line management system for optimum handling of patient care linesparticularly when rotating the bed between a supine support position anda prone support position. The risk of entanglement or dislodgement ofthe patient care lines is minimised as the lines are securely supportedby the guide means during rotation of the patient support platform.

In a second aspect, the invention is characterised in that there isprovided a retaining means for releasably securing a patient on thepatient support platform, the retaining means being operativelyconnected to the drive means for rotation of the patient supportplatform to regulate rotation of the patient support platform inresponse to correct engagement of the retaining means. This constructionadvantageously prevents rotation of the patient support platform unlessthe patient is securely strapped or otherwise restrained on the patientsupport platform. Also, it gives a simple and quick indication tonursing staff as to whether or not the patient is properly secured onthe patient support platform.

In a third aspect, the invention is characterised in that there isprovided drive means which is operable for rotation of the patientsupport platform on the base frame, means for sensing the orientation ofthe patient support platform on the base frame, and means forcontrolling operation of the drive means in response to the sensedposition of the patient support platform on the base frame. In this way,the rotation of the patient support platform can be readily controlledin a simple manner to rotate the patient support platform between anumber of desirable orientations on the base frame. Also, the basesupport platform can be controlled to move between differentorientations leaving a nurse free to attend to the patient if necessarywhile this is being carried out.

In one embodiment, means is provided for securing the patient care lineson the guide means.

In another embodiment, the guide means comprises a tubular guide forthrough passage of the patient care line or lines.

In a further embodiment, the tubular guide has a bore for throughpassage of the patient care lines and a bore insert is provided forengagement within the bore, the bore insert having a number ofspaced-apart slots about a periphery of the insert, each slot forreceipt of a patient care line, each slot being closed by a side wall ofthe bore when the insert is mounted within the bore.

In another embodiment, the guide means comprises a guide body having anumber of patient care line receiving slots for reception of the patientcare lines.

In a further embodiment, the guide means has a guide body with a numberof spaced-apart peripheral slots for reception of patient care lines.

Preferably, each slot has a side opening, and closure means is engagableacross the side opening to releasably retain a line within the slot.

In another embodiment, the closure means is a spring-loaded fingernormally biased into a slot closing position across the side opening andretractable against spring bias for insertion and removal of a line intoor from the slot.

Preferably, the closure means is a quick-release strip engagable acrossthe side opening.

In a further embodiment, the guide body is movably mounted on thepatient support platform for vertical movement of the guide body on thepatient support platform.

Preferably, the guide body is slidably mounted on the patient supportplatform.

In another embodiment of the invention, there is provided retainingmeans for releasably securing a patient on the patient support platform,

-   -   said retaining means being operatively connected to the drive        means to regulate rotation of the patient support platform in        response to correct engagement of the retaining means.

In a further embodiment, the retaining means comprises a number of pairsof support elements mounted between a head end and a foot end of thepatient support platform,

-   -   each pair of support elements comprising associated support        elements mounted on opposite sides of the patient support        platform and having a fastener to secure the support elements        together to retain a patient on the patient support platform,    -   sensing means associated with each fastener to sense correct        engagement of the fastener,    -   said sensing means being connected to a controller for        controlling operation of the drive means.

In another embodiment, each fastener has a complementary pair offastener parts, namely a first fastener part and a second fastener part,

-   -   one fastener part being mounted on each of the pair of support        elements,    -   the first fastener part being normally biased out of engagement        with the second fastener part,    -   the first fastener part co-operating with the sensor when in an        engaged position to indicate that the fastener parts are        engaged.

In a further embodiment, the sensor has a magnetically operated switchand an operating magnet is mounted on the first fastener part to operatethe switch.

In another embodiment, the support elements are mounted on side railsupstanding at each side of the patient support platform.

Preferably, each side rail is removably mounted on the patient supportplatform having means for releasably engaging the patient supportplatform,

-   -   locking means to secure the rail on the patient support        platform,    -   rail sensing means to sense interlocking engagement of the rail        with the patient support platform,    -   said rail sensing means being operatively connected to the        controller for the drive means such that the drive means will        only operate if the rail is correctly engaged with the patient        support platform.

In another embodiment, means is provided to lock each rail on thepatient support platform when the patient support platform is in aninverted position.

In a further embodiment, one or more hinged panels are provided in thepatient support platform to provide access to a patient when the patientsupport platform is in an inverted position,

-   -   each panel having panel locking means to secure the panel in a        closed position on the patient support platform,    -   panel sensing means being provided to sense locking engagement        of the panel with the patient support platform,    -   said panel sensing means being operatively connected to the        controller for the drive means such that the drive means will        only operate if the panel is locked in a closed position on the        patient support platform.

In another embodiment, there is provided means for sensing theorientation of the patient support platform on the base frame, and meansfor controlling operation of the drive means in response to the sensedposition of the patient support platform on the base frame.

In a further embodiment, the sensing means comprises a ring mounted onthe patient support platform co-axially with the rotational axis of thepatient support platform,

-   -   the ring having a first series of slots spaced at 1° intervals        about the ring,    -   the ring having a number of sets of location slots spaced-apart        about the ring, each set of location slots giving an indication        of a particular orientation of the patient support platform        relative to the base frame,    -   and a complementary position reader associated with the disc,        the position reader being mounted on the base frame and having        complementary light emitter and receiver pairs supported at        opposite sides of the disc for cooperation with the slots in the        disc to determine the orientation of the patient support        platform on the base frame.

In another embodiment, the ring has a number of parking slots locatedabout the ring defining a number of parking locations for the patientsupport platform on the base frame at which a locking bolt is engagablebetween the patient support platform and the base frame to lock thepatient support platform on the base frame.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood by the followingdescription of some embodiments thereof, given by way of example only,with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a therapeutic bed according to theinvention;

FIG. 2 is a another perspective view of the therapeutic bed, shown inanother position of use;

FIG. 3 is a further perspective view of the bed with a patient supportplatform of the bed shown in an inverted prone patient supportingposition;

FIG. 4 is an end elevational view of the bed;

FIG. 5 is a perspective view of a frame of the therapeutic bed;

FIG. 6 is a perspective view of a base portion of the bed frame with apatient support platform of the bed removed;

FIG. 7 is an elevational view of a frame of the bed;

FIG. 8 is a plan view of the bed frame shown in FIG. 7;

FIG. 9 is a plan view similar to FIG. 8 showing hinged panels of thepatient support platform in place on the bed frame;

FIG. 10 is a perspective view of the bed in use and supporting a patientin a supine position;

FIG. 11 is a perspective view of the bed in use, supporting a patient ina prone position;

FIG. 12 is a detail exploded sectional view of a side rail lockingmechanism for the bed;

FIG. 13 is a detail sectional elevational view of a side rail lockingmechanism for the bed shown in another position of use;

FIG. 14 is a sectional elevational view of a panel locking mechanism onthe patient support platform;

FIG. 15 is an enlarged detail sectional view of portion of the lockingmechanism of FIG. 14;

FIG. 16 is a view similar to FIG. 15 showing the locking mechanism inanother position of use;

FIG. 17 a is a detail perspective view of patient retaining flaps of thebed;

FIG. 17 b is a circuit diagram for a rotational interlock incorporatedin the flaps;

FIG. 17 c is a detail perspective view of a patient retaining strap andbuckle for securing the flaps;

FIG. 18 is an elevational view showing a tube guide at one end of thebed;

FIG. 19 is a detail elevational view of a rotary encoder ring formingportion of a rotational control mechanism for the patient supportplatform of the bed;

FIG. 20 is a detail side elevational view of a rotary encoder formingportion of the bed; and

FIG. 21 is a detail view showing portion of the rotary encoder ring.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings there is illustrated a therapeutic bedaccording to the invention indicated generally by the reference numeral1. The bed 1 comprises a ground engaging chassis 2 mounted on wheels 3.A base frame 4 is secured on the chassis 2 by pivot linkages 5. Rams 6housed within the base frame 4 operate the pivot linkages 5 to raise andlower the base frame 4 on the chassis 2. The rams 6 may be operated tokeep the base frame 4 level as it moves or may be operated to raise orlower one of the ends of the base frame 4 to tilt the base frame 4 abouta transverse axis of the base frame 4 to move a patient support platform7 carried on the base frame 4 into a Trendelenburg position. The patientsupport platform 7 is rotatably mounted on the base frame 4 for rotationabout a longitudinal rotational axis of the patient support platform 7between a supine support position shown in FIG. 1 and a prone supportposition shown in FIG. 3.

The patient support platform 7 has a pair of upright end rings 8,9 eachof which sits on and rotatably engages an associated pair ofspaced-apart rollers 10 (FIG. 6) at each end of the base frame 4. Sidesupport bars 12,13 extend between the end rings 8,9. A central cross bar14 extends between the side support bars 12,13. Hinged panels 16,17(FIG. 9) are hingedly connected to the cross bar 14 and can be openedwhen the bed 1 is in the prone position as illustrated in FIG. 3 foraccess to the back of a patient on the bed 1. It will be noted that thisconstruction gives good access to the patient with minimal obstruction.

A slap shut mechanism 20 (FIGS. 9 and 14 to 16) is mounted on each panel16,17 for engagement with the support bars 12,13 to securely lock thepanels 16,17 in the closed position. A spring loaded locking pin 22 isslidably mounted within an elongate tubular housing 23 for movementbetween a retracted stored position (FIG. 15) and an extended position(FIG. 16) in which the locking pin 22 engages in an associated receiverslot 23 a in the support bars 12,13. Sensors (not shown) detect correctlocking engagement of each locking pin 22 with its associated receiverslot 23 a and sends a signal to a rotational controller for the patientsupport platform 7 which prevents rotation of the patient supportplatform 7 unless both panels 16, 17 are securely locked on the patientsupport platform 7. A gravity pin 21 is slidable under gravity in anassociated tube 21 a on the housing 23 side wall for engagement with acomplementary circumferential groove 24 in the locking bolt 22 when thepatient support platform 7 is in the supine position to prevent openingof the panels 16, 17, the gravity pin 21 sliding out of engagement withthe groove 24 when the patient support platform is in the prone positionto allow opening of the panels 16, 17. A handle 98 is provided at aninner end of the locking pin 22 for manual release of the locking pin 22which can be retracted against spring 99 within the housing 23. Thus,the panels 16, 17 are released for opening. In the retracted position,FIGS. 14, 15, a spring loaded catch 100 mounted on the locking pin 22engages a slot 101 in a side wall of the housing 23 to retain thelocking pin 22 in the retracted position. The catch 100 can be pressedinto the housing 23 against spring 105 bias to release the locking pin22 which is then urged outwardly by spring 99 into the outwardlyextending engagement position shown in FIG. 16 for re-locking the panels16, 17 on the patient support platform 7.

At each side of the patient support platform 7 upstanding side rails 25are provided. Each side rail 25 has a downwardly extending stanchion 26at each end which is engagable with a complementary socket 27 (see FIG.13) in one of the support bars 12,13 of the patient support platform 7.Upon engagement of the stanchion 26 with the socket 27 a spring loadedlocking pin 28 housed within the bar 12,13 is engagable through anopening 24 in the side wall of the socket 27 with a locking slot 29 inthe stanchion 26. A handle 30 at an inner end of the locking pin 28 isoperable to slide the locking pin 28 in an associated housing 31 housedwithin the bar 12, 13 for release of the stanchion 26. A spring 31 awithin the housing 31 urges the locking pin 28 outwardly of the housing31 into a stanchion engaging position. It will be noted that anassociated gravity operated retaining pin 32 is slidably mounted in atubular casing 33 on the housing 31 such that when the patient supportplatform 7 is in the inverted prone position the pin 32 drops downwardlyunder gravity (in the direction of arrow A, FIG. 13) to preventretraction of the pin 28 locking the rails 25 in position. A sensor 35is engagable with each pin 28 to determine the position of the pin 28 toregister if the pin 28 is engaged or disengaged with the stanchion 26.All of the sensors 35 are connected in series and are connected to arotational controller for a motor which rotates the patient supportplatform 7 such that the motor will not operate until all the sensors 35indicate that the pins 28 are properly engaged with the stanchions 26 sothat the rails 25 are securely attached to and locked in position on thepatient support platform 7.

To retain a patient on the patient support platform 7, associated pairsof patient support flaps 40,41 (FIG. 1) are pivotally mounted onopposite side rails 25 and can be secured together by locking straps 43to securely retain a patient on the patient support platform 7 asdescribed in our previous patent application Publication No. WO97/22323(the details of which are incorporated herein by reference). Each strap43 comprises a web 44 with either a buckle 45 (FIG. 17) or associatedclip 46 at a free end of the web 44, the buckle 45 and clip 46 forming aquick release fastener. The web 44 when the buckle 45 is released isshortened by an elastic band 47, which is sewn in a stretched positiononto one side of the web 44, to withdraw the buckle 45 from over amagnetically operated switch 48 mounted on the associated flap 41 onwhich the buckle 45 is mounted. The magnetic switch 48 is mounted insideeach flap 41 and immediately below the magnet in the tightened buckle45. A series circuit of the magnetic switch 48 and a resistor 49terminates in a connector 49 a which is accessible on an exterior of theflap 41. By choosing a unique value of resistor for each flap 41 andmeasuring it, correct closure of each buckle 45 can be validated. Thus,when the buckle 45, which incorporates a small magnet, is in the engagedposition the magnetically operated switch 48 is operable to confirm thatthe buckles 45 and clips 46 are correctly joined and the patient is thuscorrectly secured on the patient support platform 7. Each of thefasteners must be correctly engaged before the patient support platform7 can be rotated.

A hand-held controller 85 (FIG. 4) is mounted in a pocket 86 at the footof the bed 1. This controller 85 has a contact for engagement with theconnector 49 a to allow the controller 85 to check the buckle 45 isproperly engaged (the switch 48 is closed) and determine the value ofthe resistance 48 to identify the flaps 40, 41 being checked. Each ofthe flap pairs 40, 41 are checked in sequence starting at the foot ofthe bed and moving towards the head end of the bed. Preferably, thepatient support platform 7 will not be released for rotation unless flaplocking is confirmed in the correct sequence and the sequence iscomplete. This ensures all the flaps are checked together at the sametime.

Assuming all the interlocks are clear, the hand-held controller 85 canbe used to remotely send an operating signal to the rotation motorcontroller to rotate the patient support platform 7. A nurse can movearound the bed 1 as the patient support platform 7 rotates, controllingrotation with the controller 85 to ensure there are no problems with thepatient or the patient care lines during rotation.

Management means for patient care lines such as tubes and sensor cablesis provided on the bed. At a foot end of the bed the management meanscomprises a central opening 50 (FIG. 5) adjacent a longitudinal axis ofthe patient support platform 7 for supporting and through passage of thepatient care lines. A care line holder 57 (FIG. 4) is removablyengagable within the opening 50 and has a number of spaced-apartcircumferential slots 56 each for reception of a patient care line. Eachslot 58 is closed by the side wall of the opening 50.

At a head end of the bed the patient care line management meanscomprises a guide body 51 (FIGS. 1 and 18) mounted adjacent thelongitudinal axis of the patient support platform 7 and slidable onassociated rails 52 so that it drops beneath the head of the patientwhen the bed is in either the supine or the prone position. The guide 51has a number of slots 54 for reception of patient care lines. The slots54 may be of different sizes as shown to accommodate different lines.When the patient care lines are engaged with the slots 54, a springloaded retaining finger 55 mounted across the inlets of each slot 54retains the patient care line within the slot 54. The guide body 51 ismounted on a rod 56 which is rotatably mounted on sliders 59 whichslidably engage the rails 52. Thus, the guide body 51 can be rotated outof the way for better access to a patient's head if necessary. It willbe appreciated that this patient care line management by leading thepatient care lines axially outwardly at each end of the bed greatlyfacilitates handling of the patient care lines when moving the patientsupport platform between the supine and prone support positions. Also,the patient care lines are securely held to prevent inadvertentwithdrawal from a patient.

A drive for the patient support platform can be of the type described inour Patent Specification No. WO97/22323 (the details of which areincorporated by reference), essentially comprising a belt drive betweenthe patient support platform 7 and an associated electric motor on thebase frame 4 at a foot end of the bed 1. In this case however operationof the motor is controlled by a rotary opto encoder comprising a codedisc 60 with three concentric tracks of slots 61, 62, 63, see FIGS. 19to 21 and a complementary position reader 64. An outer angle track 61comprises slots at 1° intervals. An intermediate track 62 has slots toprovide index identification and an inner index track 63 has slots inline with the lock ring park position. The disc 60 is attached to thepatient support platform 7 and the associated position reader 64 ismounted on the base frame 4. The position reader 64 has a channel 64 afor reception and through passage of an outer portion of the disc 60.Light emitters 65 are mounted at one side of the channel 64 a andcomplementary light receivers 66 are mounted at the opposite side of thechannel 64 a. The emitters 65 and receivers 66 co-operate with theassociated slots 61, 62, 63 in the disc 60 to indicate the orientationof the patient support platform 7 on the base frame 4. Seven infra-redemitter/detector pairs 65, 66 are used in the optical system to decodethe positional information. The outer track 61 comprises 360 sets ofslots 70 and spaces 71. Ideally, a slot 70 occupies 0.5 degree of thecircle, a slot 70 and space 71 together occupying 1 degree. The innertrack 63 consists of a number of narrow slots 74, each corresponding toa locking position in which an associated locking bolt 75 (FIG. 7) isengagable between the base frame 4 and the patient support platform 7.The locking bolt 75 is slidably mounted on the base frame 4 forengagement with and release from associated locking hobs on the ring 9of the patient support platform 7. The locking pin 75 serves tomechanically anchor the patient support platform 7 on the base frame 4and also operates an on/off switch for the rotation motor, preventingoperation of the motor when the locking pin 75 is engaged with thepatient support platform 7. Each slot 74 should be exactly in line withthe centre of an associated locking hole 75 a on the patient supportplatform 7, the narrowness of the slot 74 determining the accuracy oflock positioning. The intermediate track 62 is used to assign a uniquebinary code to each locking position 1. Each locking position has a setof holes 76 (varying in number from one to four holes 76). The uniquepattern of holes 76 at each locking position conveys locking angleinformation to the controller for controlling rotation of the patientsupport platform 7. The binary pattern of the holes is shown in thetable below.

Holes 76 (FIG. 21) LockPin position D C B A 1 0 0 0 1 2 0 0 1 0 3 0 0 11 4 0 1 0 0 5 0 1 0 1 6 0 1 1 0 7 0 1 1 1 8 1 0 0 0 9 1 0 0 1 10 1 0 1 0

The binary weighting of the four holes are, A=1, B=2, C=4, D=8. In thetable, the presence of a hole is indicated by 1, absence of a hole by 0.

Seven infra-red emitter detector pairs 65,66 are used in the opticalsystem to decode the positional information.

The emitter/detector pairs 65, 66 are positioned at A, B, C, D, I, X andY as shown in FIG. 21.

When a detector 66 sees an emitter 65 through a slot or hole in the disc60, it produces an output of “1”. Otherwise, it produces an output of“0”. The incremental angle and direction information are read by X andY. Every time a slot 70 passes over detector X, the angle is incrementedor decremented by one. There are two spaced-apart detectors X and Y forthe outer track 61 and the order in which the detectors X and Y see theemitter determines the direction. There are four spaced-partemitter/detector pairs A, B, C, D associated with the intermediate track62 and these supply the pattern information to the controller to computethe locking angle information. There is one emitter/detector pair Iassociated with the inner track 63 and this supplies the lockingposition information. As the patient support platform 7 rotates thespaces between the slots interrupt infra-red beams passing betweenemitters 65 and receivers 66 on a support 67 on the base frame 4.Information from the infra-red detectors is processed by an opticalprocessing controller to provide the angle of the patient supportplatform 7 which is indicated on a display screen 80 (FIG. 4) at a footend of the bed 1.

As can be seen in FIG. 7, the pivot linkages 5 have pivot arms 90, 91having inner ends which pivotally engage the base frame 4 by pivot pins92, 93. At one end of the bed 1, an outer end of each pivot arm 90pivotally engages the chassis 2 by a pivot pin 94, while at the otherend of the bed 1, the outer end of each pivot arm 91 pivotally engagesthe chassis 2 by pivot pins 95 which are also longitudinally slidable inelongate slots 96 on the chassis 2. The rams 6 are operable to rotatethe pivot pins 92, 93 on the base frame 4 for operation of the pivotlinkages 5.

In use, sensors associated with the side rails 25 and the panels 16, 17on the patient support platform 7 are connected to the drive controllerfor the patient support platform 7 such that the patient supportplatform cannot be rotated unless all the locks are correctly engaged.Further the sensors for the straps of the patient retaining flaps 40, 41also need to indicate correct engagement before the patient supportplatform 7 can be rotated. It will also be appreciated that the deliveryof the patient care lines such as tubes and other cables and conduitsaxially outwardly at each end of the patient support platform greatlyfacilitates management of the patient care lines during movement of thepatient support platform between the supine and prone positions.

It will be noted that when the patient support platform is rotated fromthe supine support position into the prone support position, it willrotate through 200° and then return to the 180° or zero prone position.This function will centre the patient on the bed 1.

It will be appreciated that the patient support platform may beoscillated on the base frame or may be locked in a number of fixedorientations on the base frame.

It will also be appreciated that the invention provides a patient careline guide system for a hospital bed for neatly guiding patient carelines off each end of the bed.

The invention is not limited to the embodiments hereinbefore describedwhich may be varied in both construction and detail within the scope ofthe appended claims.

1. A therapeutic bed comprising: a base frame, a patient supportplatform rotatably mounted on the base frame for rotational movementabout a longitudinal rotational axis of the patient support platform, amotor operable to rotate the patient support platform on the base frame,and a guide body defining one or more patient care line receiving slotsoperable to guide one or more patient care lines from an apparatusexternal of the patient support platform to a patient on the patientsupport platform.
 2. A therapeutic bed as claimed in claim 1, whereinthe guide body is mounted on the patient support platform.
 3. Atherapeutic bed as claimed in claim 1, further comprising a bore forthrough passage of the patient care lines and wherein the guide bodycomprises a bore insert that is provided for engagement within the bore,the bore insert defining a number of spaced-apart slots about aperiphery of the insert, each slot for receipt of a patient care line,each slot being closed by a side wall of the bore when the insert ismounted within the bore.
 4. A therapeutic bed as claimed in claim 1wherein the slots are spaced apart along the periphery of the guidebody.
 5. A therapeutic bed as claimed in claim 1 wherein each slot has aside opening, and a spring-loaded finger normally biased into a slotclosing position across the side opening and retractable against thespring bias, the finger facilitating secured retention of a line andalso facilitating insertion and removal of a line into or from the slot.6. A therapeutic bed as claimed in claim 1 wherein each slot has a sideopening and a quick-release strip engagable across the side opening. 7.A therapeutic bed as claimed in claim 1 wherein the guide body ismovably mounted on the patient support platform.
 8. A therapeutic bed asclaimed in claim 1 wherein there is provided a plurality of pronesupport elements mounted between a head end and a foot end of thepatient support platform for releasably securing a patient on thepatient support platform, said prone support elements being operativelyconnected to the motor to regulate rotation of the patient supportplatform in response to correct engagement of the plurality of pronesupport elements.
 9. A therapeutic bed as claimed in claim 8 wherein theplurality of prone support elements comprise matching pairs of supportelements mounted on opposite sides of the patient support platform andfasteners to secure the matching support elements together to retain apatient on the patient support platform, sensors associated with eachfastener that sense correct engagement of the fastener, said sensorsbeing connected to a controller for controlling operation of the motor.10. A therapeutic bed as claimed in claim 9 wherein each fastener has acomplementary pair of fastener parts, namely a first fastener part and asecond fastener part, one fastener part being mounted on each of thepairs of support elements, the first fastener part being normally biasedout of engagement with the second fastener part, the first fastener partcooperating with the sensor when in an engaged position to indicate thatthe fastener parts are engaged.
 11. A therapeutic bed as claimed inclaim 10 wherein the sensor has a magnetically operated switch and anoperating magnet is mounted on the first fastener part to operate theswitch.
 12. A therapeutic bed as claimed in claim 9 wherein the supportelements are mounted on side rails upstanding at each side of thepatient support platform.
 13. A therapeutic bed as claimed in claim 12wherein each side rail is removably mounted on the patient supportplatform having means for releasably engaging the patient supportplatform, locking means to secure the rail on the patient supportplatform, rail sensing means to sense interlocking engagement of therail with the patient support platform, said rail sensing means beingoperatively connected to the controller for the motor such that themotor will only operate if the rail is correctly engaged with thepatient support platform.
 14. A therapeutic bed as claimed in claim 12wherein means is provided to lock each rail on the patient supportplatform when the patient support platform is in an inverted position.15. A therapeutic bed as claimed in claim 1 wherein one or more hingedpanels are provided in the patient support platform to provide access toa patient when the patient support platform is in an inverted position,each panel having panel locking means to secure the panel in a closedposition on the patient support platform, panel sensing means beingprovided to sense locking engagement of the panel with the patientsupport platform, said panel sensing means being operatively connectedto a controller for the motor such that the motor will only operate ifthe panel is locked in a closed position on the patient supportplatform.
 16. A therapeutic bed as claimed in claim 1 wherein there isprovided means for sensing the orientation of the patient supportplatform on the base frame, and means for controlling operation of themotor in response to the sensed position of the patient support platformon the base frame.
 17. A therapeutic bed as claimed in claim 1, furthercomprising a ring mounted on the patient support platform coaxially withthe longitudinal axis of the patient support platform, wherein the ringhas a number of parking slots located about the ring defining a numberof parking locations for the patient support platform on the base frameat which a locking bolt is engagable between the patient supportplatform and the base frame to lock the patient support platform on thebase frame.
 18. A therapeutic bed comprising: a frame; a patient supportplatform mounted on the frame and rotatable about a longitudinal axis ofrotation through substantially 180° from a patient face-up or supineposition to a patient face-down or prone position; the patient supportplatform comprising a hinged section that provides access to the backside of a patient when the patient support platform is in the proneposition; a plurality of prone patient supports mounted to oppositesides of the patient support platform; and a motor operationally engagedwith the patient support platform to move the patient support platformfrom the supine position to the prone position and to oscillate thepatient support platform about an arc of rotation intersecting the proneposition.
 19. The therapeutic bed of claim 18, wherein at least some ofthe prone patient supports are hingedly mounted to the patient supportplatform.
 20. The therapeutic bed of claim 18, wherein at least some ofthe prone patient supports are split adjacent the longitudinal axis ofrotation of the patient support platform.
 21. The therapeutic bed ofclaim 20, wherein at least some of the prone patient supports areoperable to be locked to each other.
 22. The therapeutic bed of claim21, wherein at least some of the prone patient supports are hingedlymounted to the patient support platform.
 23. The therapeutic bed ofclaim 20, wherein at least some of the prone patient supports areoperable to be locked to each other with fasteners.
 24. The therapeuticbed of claim 20, wherein at least some of the prone patient supports areoperable to be locked to each other with straps and fasteners.
 25. Thetherapeutic bed of claim 18, the patient support platform having siderails extending upwardly from opposite lateral sides of the patientsupport platform, at least some of the prone patient supports beingmounted to the side rails of the patient support platform.
 26. Thetherapeutic bed of claim 25, wherein at least some of the prone patientsupports are hingedly mounted to the side rails of the patient supportplatform.
 27. The therapeutic bed of claim 26, wherein at least some ofthe prone patient supports are split adjacent the longitudinal axis ofrotation of the patient support platform.
 28. The therapeutic bed ofclaim 27, wherein at least some of the prone patient supports areoperable to be locked to each other.
 29. The therapeutic bed of claim27, wherein at least some of the prone patient supports are operable tobe locked to each other with fasteners.
 30. The therapeutic bed of claim27, wherein at least some of the prone patient supports are operable tobe locked to each other with straps and fasteners.
 31. The therapeuticbed of claim 18, wherein one of the prone patient supports is an abdomensupport adjustable to accommodate abdomens of varying sizes.
 32. Thetherapeutic bed of claim 31, wherein the abdomen support is comprised ofa flexible material.
 33. The therapeutic bed of claim 18, wherein atleast one of the prone patient supports comprises a strap to support thepatient's head.
 34. The therapeutic bed of claim 18, wherein the pronepatient supports comprise a head support section separately adjustablefrom a shoulder and upper body support section separately adjustablefrom an abdomen support section separately adjustable from a lower bodysupport section.
 35. A therapeutic bed comprising: a frame; a patientsupport platform rotatably mounted on the frame about a longitudinalaxis of rotation, the patient support platform being rotatable from apatient face-up or supine position to a patient facedown or proneposition; a motor operationally engaged with and operable to rotate thepatient support platform from the supine to the prone position and toalternately rotate the patient support platform about the longitudinalaxis of the bed through an arc of alternating rotation substantiallycentered at the prone position; and prone patient supports operable toretain a patient on the patient support platform and to provide supportto the patient while the patient support platform is rotated from thesupine to prone position and while the patient support platform isalternately rotated through said arc of alternating rotation; whereinthe therapeutic bed is operable to provide lateral rotation therapy tothe patient while the patient is in the prone position.
 36. Thetherapeutic bed of claim 35, wherein the motor is operationally engagedwith and operable to rotate the patient support platform through an arcof alternating rotation spanning from between positive 15 to 62 degreesfrom the prone position to a negative 15 to 62 degrees from the proneposition.
 37. The therapeutic bed of claim 35, further comprising a pairof side rails extending upwardly from the patient support platform. 38.The therapeutic bed of claim 37, wherein the side rails are operable tobe displaced from their upwardly extending position on the patientsupport platform to facilitate mounting of patients on the patientsupport platform.
 39. A therapeutic bed comprising: a frame; a patientsupport platform mounted on the frame and rotatable about a longitudinalaxis of rotation through substantially 180° from a patient face-up orsupine position to a patient face-down or prone position; a pair of siderails extending upwardly from the patient support platform; and a amotor operationally engaged with the patient support platform to movethe patient support platform from the supine to the prone position andto provide controlled rotational movement to the patient supportplatform.
 40. The therapeutic bed of claim 39, wherein the side railsare operable to be displaced from their upwardly extending position onthe patient support platform to facilitate mounting of patients on thepatient support platform.
 41. The therapeutic bed of claim 40, whereinthe side rails are operable to be locked into their upwardly extendingposition on the patient support platform.
 42. The therapeutic bed ofclaim 39, further comprising prone patient supports mounted to the siderails.
 43. The therapeutic bed of claim 42, wherein the side rails areoperable to be displaced from their upwardly extending position on thepatient support platform to facilitate mounting of patients on thepatient support platform.
 44. The therapeutic bed of claim 43, whereinthe side rails are operable to be locked into their upwardly extendingposition on the patient support platform.
 45. A therapeutic bed operableto provide lateral rotational therapy to a patient in both the supineand prone positions, the bed comprising: a frame; a patient supportassembly mounted on the frame; wherein the patient support assemblycomprises a patient support platform mounted on a circular structurehaving a center and a perimeter, the patient support assembly beingrotatable about a longitudinal axis of rotation through substantially180° from a patient face-up or supine position to a patient face-down orprone position; wherein the longitudinal axis of rotation of the patientsupport assembly intersects the center of the circular structure;wherein load from the patient support assembly is transferred to theframe through the perimeter of the circular structure; and a motoroperationally engaged with the patient support assembly to move thepatient support platform from the supine position to the prone position.46. The therapeutic bed of claim 45, wherein the circular supportcomprises at least one ring-shaped rail.
 47. The therapeutic bed ofclaim 45, wherein the perimeter of the circular support isbarrel-shaped.
 48. The therapeutic bed of claim 45, wherein the circularsupport is cylindrically shaped.
 49. The therapeutic bed of claim 45,wherein the circular support is mounted on guide rollers on the frame.50. The therapeutic bed of claim 45, further comprising prone patientsupports mounted to opposite sides of the patient support assembly. 51.The therapeutic bed of claim 50, wherein the patient support assemblyfurther comprises side rails extending upwardly from the oppositelateral sides of the patient support assembly.
 52. The therapeutic bedof claim 51, wherein at least some of the prone patient supports aremounted to the side rails.
 53. The therapeutic bed of claim 52, whereinat least some of the prone patient supports are hingedly mounted to theside rails.
 54. A method for treating a patient with respiratoryproblems comprising: securing a patient to a mechanically poweredpatient support platform; rotating the patient from a substantiallysupine position to a substantially prone position; and alternatelylaterally rotating the patient about a longitudinal axis of the bedacross an are spanning from between positive 15 to 62 degrees from theprone position to a negative 15 to 62 degrees from the prone position.55. A method for treating patients with adult respiratory distresssyndrome comprising: securing a patient to a mechanically poweredpatient support platform; rotating the patient from a substantiallysupine position to a substantially prone position; and alternatelylaterally rotating the patient about a longitudinal axis of the bedacross an arc spanning from between positive 15 to 62 degrees from theprone position to a negative 15 to 62 degrees from the prone position.